812441821 has 2 divisors, whose sum is σ = 812441822. Its totient is φ = 812441820.

The previous prime is 812441803. The next prime is 812441837. The reversal of 812441821 is 128144218.

812441821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 725224900 + 87216921 = 26930^2 + 9339^2 .

It is a cyclic number.

It is not a de Polignac number, because 812441821 - 2⁵ = 812441789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (812441801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406220910 + 406220911.

It is an arithmetic number, because the mean of its divisors is an integer number (406220911).

Almost surely, 2^812441821 is an apocalyptic number.

It is an amenable number.

812441821 is a deficient number, since it is larger than the sum of its proper divisors (1).

812441821 is an equidigital number, since it uses as much as digits as its factorization.

812441821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4096, while the sum is 31.

The square root of 812441821 is about 28503.3650820390. The cubic root of 812441821 is about 933.1055164915.

The spelling of 812441821 in words is "eight hundred twelve million, four hundred forty-one thousand, eight hundred twenty-one".